Telegraphic system.



- v PA'TENTED'MAY 15 1906. J. W. LATTIG, c. L. GOODRUM & E. E. CLEMENT.

TELEGRAPHIG SYSTEM.

APPLICATION FILED JUNE 9 1903 2o way in which we attain a great many advantages of tele raphic service on moving trains, this graphic messages passing to all the stations reached every employed who are not highly-skilled experts,

UNITED STATES PATENT OFFICE.-

JACOB W. LATTIG, OF WEST BETHLEHEM, AND CHARLES LANE GOCD- RUM, OF PHILADELPHIA, PENNSYLVANIA, AND EDWARD E. CLEMENT, OF WASHINGTON, DISTRICT OFCOLUMBIA.

TELEGRA-PHIC SYSTEM.

N 0. 820,652. Specification of Letters Patent. Patented May 15, 1906.

Application filed June 9, 1903. Serial No. 160,750. To all whom it may concern:

Be it known that we, JACOB W. LATTIG, residing in West Bethlehem, Lehigh county, and CHARLEs LANE GooDRUM, residing in Philadelphia, county of Philadelphia, Pennsylvania, and EDWARD E. CLEMENT, residing in Washington, District of Columbia, citizens ofthe United States, have jointly invented a new and useful Telegraphic System, of which the following isaspecificati'on. v 4

Our invention relates to telegraphic systems, and more particularly tothose in which lines are employed to serve way-stations. Such lines usually pass through all the stations in series, all instruments being included directly therein. Circuitsof this kind are frequently-employed in railway service for communicating between train despatchers and line 0 erators, as well as in ordinary commercia work. We have discovered a can double the capacity for transmission over such a line and incidentally value in themselves. Thus ithas heretofore not been economically possible to maintain regular I such operators bein frequently good transmitters but very s ow recelvers. Thus a crew, such as the bagga e-master, and only so much of his time wil be taken from his regular duties asmay be required by messages sent to and from his own train.

Our invention is not limited to train serv ice, being applicable to any line and'particularly any way-station line. i

It consists, essentially,- in the application of coherers in the manner disclosed by Edward E. Clement in Patents'Nos. 719,998 and 719,999, issued February 10, 1903, to systems of the character described, using superposed currents or impulses of suitable character to operate the. coherers, but of unsuitable character to operate the ordinary relays at the way-stationson the line. i

Our invention is fully described hereinafter and illustrated in the accompanying drawing, in which the figureis a diagram of a system embodying our invention.

Referring to the drawing, 1 is a line-circuit extendingthrough three way-stations U,-V, and passing in series through the relays R, R, and R and the normally closed keys K, K, and K These keys are shunted by circuits 2, 3, and 4, C, and C The relays R, 850., throughtheir armatures r, 1", and r respectively,'control resu lting from the fact that ordinary 'tele-' station and the only way any operator could tell what messages were intended for him would be by constant listening. This meant the use of a telephone-receiver, articularly because/she impulses inductive y received on a moving train were very weak: For these reasons it will be observed that to give continuous service it would require the entire time of one man, and this would mean the addition of a telegraph operator to every train crew, with the likelihood that outside of the train-orders not enough business would pass through his hands even on long runs to pay more than a small fraction of his salary and expenses.

In order to make train telegraphy commercially feasible, it must be ossible to call up the train when wanted and only for traindespatches, giving a signal that will be loud enough or conspicuousenough to attract the attention of the operator while engaged in other duties, and the signals'received must be of such a nature that they can be recorded in the ordinary "way, so that operators may be S current for these being supplied by the local batteries 12, b, and 6 IV hen a signal is to be transmitted from one to any other, its key K is opened at a tlme when the relay is not working, and by then manipulating it all the relays along the line may be effected, current being supplied thereto by the generators B B. he currents tirely, which are passed through R, &c., but'do not penetrate the condensercircuits 2, 3, and 4. These condensers, howclass of currents, which we superpose on the line, which may be alternating currents. or high frequency broken or periodic currents of from an induction-coil having an interrupter in its primary. In addition to the stations railroad would be enabled to make the telegraph operator a regular member of the train containing condensers C,

sounders or recorders, (indicated at S,S, and

of these stations used over'the circuit 1 are direct currents enthe relays- U, V, and W we carry the line to stations-X,

ever, make the line practicable for another any kind, such as the succession of impulses 6 and not t Y, and Z. This may be by means of a conductive connection or an inductive connection through coils or condensers, as shown, and the stations X, Y, and Z may be stationary or they may be movable, like cars on a railroad. In the latter case the connections would be inductive, preferably, the instruments in the car being connected to the carroof or other extended metal coating and the communication between that and the line along the tracks being by electrostatic effect. It is quite feasible to have the car provided with a brush to travel on a conductor rail or wire, however, and in suchcase the connection would be conductive and more'positive, also more expensive.

From the line'l taps 5, 6, and 7 are taken off to the stations X, Y, and Z, respectively, either inductive or conductive, as staterl. The wire 5 passes to a relay R thenceto the secondary winding 1', of an induction-coil I, and thence to ground. A branch 50 is taken around the relay R and includes the coherer M. The relay R has its armature included.

in and controlling a local circuit 500, in which are connected in parallel the recorder orsounder S and the coherer-tapper Twith a local battery 6 At stations Y and Zthe pants and connections are'the same as at station X, the lettering being the same with different exponents to distinguishthe station.

The operation of our system is as follows: Messages are sent over the main circuit 1 in the usual mannerby means of makes and breaks in the direct current supplied by the. generators B and B, for such currents the 'Eath beingclosed only through the relays and eys. This service goes on without reference to that between stations X, Y, and Z, and calls are interchanged between those stations Whether the line is busy or not. If X desires to call Ysay the train-despatcher desires to call train No. 147-he uses key K listening first, as in every way-station system, to see if the line is in use by station-Y or Z. The key K in closing starts current from battery I) through the circuit 8 and the primary of induction-coil I, whereupon the secondary 'i sends'to line a rapidly-alternating set of impulses, due to the breaks in the primary caused by the vibrating armature or other circuit-breaker in the circuit 8. The path for these impulses is through condenser, ca-

'pacity, or conductor (as the case may be) C to line 1 and then 'over the same to-all the stations of the coherer type going by preference throggh the condensers C, C, and C ough the relays R, R], 'or R on account of their high inductance. Thus no disturbance is produced in the relay-circuits. At each station .Y'or Z this-alternatingcurrent comes to ground through the coherer and the secondary t, the first impulse or set of impulses causing the coherer; to set, its re-- sistance to be lowered, and the local circuit composed of conductors 6 and or 7 and to be closed through its battery I) or b. As this local circuit includes the relay R or R the armature thereof is drawn up and the cir- .cuit 600 or 700 is closed, causing current from battery b" or b to affect the recorder or sounder S S and the tapper T T to restore the coherer to its usualcondition of high resistance. Operator at station X can thus call either of the other stations and after receiving an answer can transmit the message, or the call can be made, and. then-if a recorder is-used at each station the message can be sent along and being recorded can be read and transcribed afterward.

Our invention solves a serious roblem in railway telegraphy and is usefu in many other fields. I

We are aware that many changes can be made in the matter of details, and all such we include within the scope of our claim. For instance, self-restoring or what are called self-decohering coherers can be used, when the tapper T can be dis ensed with, alternating current can be use from a generator instead of the induced current from an induction-coil, &c. suitable and desired form, those we have found preferable being of the type designed by Professor Oliver Lodge, which are well known, consisting of tubes of filings or other granulated material. These coherers can also be replaced by other sensitive-devices without de arting from the invention, the gist of whic is to normally hold the stations out of circuit in an operative sense, so that ordinary signals do not pass, but to bring them in for calling purposesat will. We shall use the terrn"sensiti-ve resistance device in the claim to designate the coherer or any equivalent device useful in our sys ,tem. We shalluse the words opaque and transparent also in the sense in which they are employed in the patents to Clement ab ove referred tothat is, opaque as stopping the current from passing and transparent as permitting it to pass. sion a connection from each station to ine or its equivalents as meaning any sort of connection by which the impulses to affect the coherers or their equivalents may be passed. Thus the line-wire along the track might receive the same sort of Waves as those used in 'so-called"space telegraphy, broadly serving as a continuous antenna, and in. such case the ears of a train carrying the coherers Imght be fitted with wires to receive the wave 1m- The coherers can be of any We shall usethe ex res-.

pulses similar to the vertical wires similarly employed. In fact, if electrostatic effects are to be assisted by Hertz Waves no receiving wires need be provided, or very short ones, a surface being sufficient.

' In using this system .for train-orders it seems that the best and most reliable method a predetermined manner to ca "usual mode C &c., and-1C &c.

. duce rapi in said conductor, a vehicle'adapted to move would be to keep a constant succession of impulses normally on the line, stop ing them in y rangement would thus announce itself, and that certainty would be attained that isso necessary in railway matters. We shall include this in our claim, as it reverses the of operation. and is a valuable feature.

At each of the stations X and Z we'have shown a telephone. in a branch wire 11. After a station has been called the tele hones can be used in the ordinary wa cond ensers assingt e'tele honic currents perfectly. 'Fhis is also feasi le on. moving cars by induction or. otherwise, and

it "should be stated that in such case the grounds 12 would be made through the car'- Wheels.

Having thus described our invention, what ...-we'c1aim', and desire to secure by Letters Patent, is- 7 v Ina system of railway communication, the combination with the following instrumentalities: a continuous conductor and a line of rails in roximity thereto, means to prodl -changing electromotive forces' signed our names in the cuit containing a battery and a signa -receiv ing device, together with a coherer or similar mounted'upon said vehicle and moving there with in constant inductive relation to the fixed conductor, a connection from said body to the radiosensitive device and to groun. a telephone instrument on thevehicle-also upon'said rails, a normally open si al-cirradiosensitive device, a conducting body connected to said body and to ground, andand signal device, an may thereafter communicate by means of the telephone while the vehicle is in motion, substantially as described. y

In witness whereof we have hereunto presence of two subscribing witnesses.

JACOB W. LATTIG. CHARLES LANE GOODR-UM. EDWARD E. CLEMENT.

Witnesses: v

MAGGIE J. SooTr, M. S. LEWIS. 

